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(No Model.) I

N .,.W. PRATT. MULTIPLE PRIMER FOR SHELLS. No. 388,787.

,INVENTOR,

ATTORNEY w. PEYERS, PhuIo-Lnhngnphen wamm vm D, c.

Patented Aug. 28, 1888.

NAT. W. PRATT, OF BROOKLYN, ASSIGNOR TO THE PNEUMATIC DYNAMITE GUN COMPANY, on NEW YORK, N. Y.

MULTIPLE PRllVlER FOR SHELLS.

SPECIFICATION forming part of Letters Patent No. 388,787, dated August 2 Application filed June 28, 1886.

To all whom it may concern.-

Be it known that I, NAT. W. PRATT, a citizen of the United States, residing at the city of Brooklyn, county of Kings, and State of New 5 York, have invented certain new and useful Improvementsin Multiple Primers for Explosive Shells, of which the following is a specification, reference being had to the accompanying drawings, forming a part of the same, in

which Figure l is a longitudinal section; Fig. 2, a transverse section on the line as 00, on an enlarged scale; Fig. 3, a detail view of a part of Fig. 2; Fig. 4, a side elevation, partly in seetion, of the primer-case; Fig. 5, a partiallyseetioned elevation of the same, viewed in a plane at a right angle to that of Fig. 4, and Fig. 6 a detail view of the primers.

This invention relates to elongated projectiles used in ordnance in which explosive contents within are ignited and discharged by the concussion of the projectile upon the obstacle which terminates its flight; and it consists of certain devices by which the ignition is better insured and timed than by former devices and the manipulation of the parts facilitated; and in order that others may understand and use my said invention 1 will proceed to describe the same in detail and explain its operation,

and subsequently point out in the appended claims its novel characteristics.

Referring to the accompanying drawings, in which like lettcrsindicate like parts throughout the several views, the body A of the pro- 5 jectile, Fig. 1, is cast hollow for the reception of explosive material, which is introduced through the opening at its rear end, into which a plunger-case, B, is fitted, and secured in place by a screw cap or plate, 0.

The plunger-case B is provided with four or any desired number of holes or barrels, a, into which are loosely fitted the several plungers I), having the projecting tips 0 at their forward end,which correspond in position with the opposite fulminate percussion-fuses,d, in the cap D of said plunger-ease. The plnngers b are further provided near their rear ends with the circumferential grooves 0,0f semicircular form in cross-section, in which aspringlock-bolt,f,

passes between the plungers in the manner shown in Fig. 6. The spring compressed Serial No. 206.457. (No model.)

between the seat It and collar i of the bolt f, tends to force the said bolt outward until the collar 2' stops against the bushing j, which is screwed into the casing B, and through which 5 the bolt f is free to slide when released. When the bolt f is released, its reduced portion 7a assumes the position shown in Fig. 3, whereby itslargerportions,f and f, clear the grooves c of the plungers b, and leave them free to pass out of the barrels a at the moment of impact. The boltf abuts against the main boltf,which coincides in continuation with it through the shell A when the plunger-case B is placed in position. A loekspring, Z, having a pin, m, 6 engaging with the collar t of the spring-bolt, serves to keep the same in its locked position when the case B is out of the projectile. When said case is inserted in place, the spring Z is withdrawn by contact of its projecting end with the shouldern of the shell. At this time the spring-boltf and bolt f are held back by a temporary collar, E, kept upon the butt of the projectile until used by means of a thumbscrew, 0, entering the circumferential groove 7 p. The cap D is made longitudinally adjustable on theplunger-case B, being guided thereon by its sleeve D, which fits freely over the smaller diameter of the said case, and is kept from turning by a slot, q, and stud awhile the adjusting bolt 8, tapped into the casing 13 and having a square head and a collar, t, may be turned to determine the adjustment in either direction.

In operation the projectile is inserted in the breech of the gun by removing the collar E, whereupon the bolt f rests against the interior of the bore.

Upon firing the gun the position of the parts herein described remains unchanged until the 0 projectile is delivered, at which time the springbolt f f, released and thrown out, leaves the plungers b to be retained by their inertia within the chambers to during the flight of the projectile. At the moment of impact the plun 5 gcrs impinge against the fulminates d, which exploding ignite the charge in the shell.

The multiple plungers insure against failure of explosion in event of the nonaction. of one or part of their number from any cause.

The adjustment of the cap I) minutely determines the interval between the impaet of the projectile and its explosion, the distance through which the plungers I) must travel being regulated thereby.

Having thus fully described my invention, What I claim, and desire to secure by Letters Patent, is

1. A projectile for carrying an explosive charge provided with a series of independent plungers for exploding the fnlininates, a series of independent fulminates mounted clear of the plungers, and a lock for normally holding said plungers positively against movement toward the fulminates, but automatically unlocked when the projectile leaves the gun, such plungers being then kept from impingement against the fulminates by inertia, substantially as described.

2. A projectile provided with a series of,

plungers for exploding a fulminatc, a series of fulminates in position to be exploded by said plungers, and a case for containing said plungers and fulminates, having an adjustable end to vary the distance between the striking-point of the plungers and the fulminates,whereby to regulate the time utilized to explode the charge after the projectile strikes an object or is embedded therein.

3. A projectile provided with a plurality of plungers for exploding a fulminate, a springseated bolt for locking the plungers in position when placed in the projectile or in the barrel of a gun, and a temporary collar adapted to be placed upon the butt of the projectile when out of the gun to hold the bolt in its locking position, substantially as described.

4:. A primencase for projectiles provided with aplurality of plungers for exploding a fulminate, a spring-seated bolt for locking the plunger-s in position, and aspring-pin for normally holding the bolt in its locking position, and adapted to be disconnected to free the bolt when the case is inserted in place in the projec' tile by the engagement of the spring with the wall of the projectile, substantially as described.

5. In a projectile, the combination, with a case having chambers containing plungers for exploding a fulminate, of a lead to said case provided with the fulminate and sustaining it a distance removed from the points of the pl un gers, and an adjusting-screw for adjusting the position of the lead to vary the distance between thefulminate and plungcrs,substantially as described.

NAT. \V. PRATT.

\Vitnesses:

CHAS. W. FoRnns, AUG. CREVELING. 

